The Giants ace made his second rehab start since suffering a Grade 2 sprain of his throwing shoulder, appearing for the Giants Class A affiliate in San Jose on Wednesday night. It did not go well at all, as Bumgarner was roughed up for nine runs on nine hits over four innings.

Among those nine hits were four home runs. Three of those home runs came during an eight-run fourth inning by the Rancho Cucamonga Quakes, the Class A affiliate of the Dodgers. Two of those fourth-inning homers were stroked by one batter:

Well, DJ Peters just hit 2 HRs in one inning against Madison Bumgarner.

D.J Peters started the rally with a solo home run against the former World Series MVP. Then he capped it with a two-run home run. In between second baseman Drew Jackson smacked a three-run homer.

Peters was a fourth round pick of the Los Angeles Dodgers in the 2016 draft and has quickly become a well-regarded prospect in the organization. He’s a good hitter with some clear power potential — the homers were his 17th and 18th of the season — but it’s pretty stunning to see any player do this type of damage against Bumgarner.

Bumgarner’s final line against this Class A lineup was actually worse than any start he’s had at the major league level.

Madison Bumgarner allowed 9 ER and 4 HR in a rehab start tonight; his career highs in 221 MLB appearances are 8 ER and 3 HR

Bumgarner was also far from sharp in his first rehab outing at Triple A Sacramento on June 30. He allowed four runs in 3 2/3 innings in a loss against a red hot Fresno team. But the lack of effectiveness was anticipated there with Bumgarner making his first start in over two months. It was at least hoped he’d look a little sharper on Wednesday, but that clearly wasn’t the case.

The Giants are not panicking though. The main focus for them at this stage in Bumgarner’s rehab is that he’s feeling good physically. In that regard, he actually cleared a big hurdle.

“It would have been nice to get up and down one more time but we got the pitch count up and that’s ultimately all we’re looking for,” Bumgarner said courtesy of CSN Bay Area. “I felt good with the way my body felt. The command felt good. Obviously that’s kind of a lopsided outing but my body feels pretty good.”

Bumgarner tossed 76 pitches on Wednesday, and acknowledged that he wasn’t dipping into his full repertoire in an effort to dominate. That number should get over 90 pitches in his next scheduled rehab outing with San Jose, which Bumgarner also hopes will be the last.

Bumgarner says he plans to feature his “bread and butter” pitches a little more in that outing. Assuming the shoulder continues feeling good and he’s not knocked around the park to the extent of Wednesday’s game again in that outing, he should be back in the Giants rotation the weekend after the All-Star break.